Process for creasing fabrics containing nylon



United States Patent Office 3,497,583 Patented Feb. 24, 1970 3,497,583 PROCESS FOR CREASING FABRICS CONTAINING NYLON Lawrence Francis OBrien, Jr., Newark, Del., assignor to E. I. du Pont de Nemours and Company, Wilmington, Del., a corporation of Delaware No Drawing. Filed June 19, 1967, Ser. No. 647,216 Int. Cl. B29g /00; D21j 3/00 U.S. Cl. 264136 4 Claims ABSTRACT OF THE DISCLOSURE A process for imparting durable creases to polyamide containing textile material which includes the steps of 1. applying an aqueous solution of an organic swelling agent for the polyamide to the area of the textile material where the crease is to be formed, 2. allowing the treated material to lag from one to 120 minutes, and 3. pressing the crease at a temperature between 120 C. and 170 C.

This invention relates to a process for imparting durable creases to polyamide containing textile materials in order to provide creases that are durable through hand and machine washing as well as normal wear.

The use of resin-treatments to enhance the wrinkle resistance and retention of creases in fabricated garments made of cellulosics or wool is well known. Similarly, the application of solutions such as solvents or swelling agents to localized areas of these garments where creases are to be imparted by pressing, has been practiced for many years. It is also known that polyamide fabrics, particularly, polyamides blended with cellulosic fibers in order to impart durability, can be treated with organic solvents in order to reduce pilling or to affect the hand, luster or tactile aesthetics.

The object of this invention is to provide a process for imparting durable creases and pleats in fabrics and garments containing at least a portion of polyamide fibers by the use of an aqueous solution of organic swelling agent with a lag time before pressing at an elevated temperature. The process is equally applicable to resinfinished polyamide'containing fabrics and garments. It is particularly applicable to fabrics which contain continuous filament polyamide yarns and to fabrics made from spun yarns containing more than 50% polyamide staple fiber.

As organic swelling agents which are at least partially water soluble, there may be used benzyl alcohol, cyclohexanol, and phenolic compounds such as phenol, cresol, and the like. In addition, amides such as formamide and dimethyl formamide, esters such as butyl benzoate and methyl salicylate, and aliphatic straight chain alcohols or acids containing from 7 to 10 carbon atoms are suitable. The organic swelling agent may be added in a concentration of from 5 to 40% by weight of the aqueous solution with a preferred range being from about 10 to about 35%. It is sometimes advantageous to use an auxiliary solvent such as ethyl alcohol in combination with water, in order to increase the solubility of the swelling agent to attain the desired concentration.

In carrying out the process of the invention, the fabric is sprayed with the aqueous solution of the organic swelling agent for the polyamide fiber in the area where the crease is to be formed. The treating solution can also be applied in other ways such as padding, painting, dipping, or printing. The treated fabric is allowed to lag from one to minutes before pressing the crease, which may be accomplished in a number of ways. The preferred procedure is the use of a conventional hot head press operated at a temperature between 120 C. to C. with the press locked for about 20 seconds. Surprisingly, a shorter lag time has been found to give improved crease durability to machine laundering while a longer lag time reduces crease durability. While not wishing to be held to this explanation, it is theorized that this surprising discovery is a result of the reduced wicking action of the fabric on the applied organic swelling agent when a shorter lag time is used. Apparently, by allowing wicking to take place from the treated area of the fabric to the surrounding untreated area of the fabric, the effect of the organic swelling agent is diminished.

The durability of the imparted crease is tested by submitting the creased article to 10 laundry cycles as described in the American Association for Textile Chemists and Colorists, Test 88C-1964T, except that the water temperature was 100 F., the wash time was 5 minutes, and 30 grams of detergent were used. The washed creases are rated by a panel of judges and assigned a value rating from 1 to 5, as described in A.A.T.C.C. 88C-1964T in which the ratings have the following meanings:

Rating No change 5.0 Slight change -1 4.0 Moderate change 3.0 Considerable change 2.0 Severe change 1.0

The following examples are illustrative of the process of this invention. All parts and percentages are by weight.

EXAMPLE I A 7.3 oz./yd. corduroy fabric containing 100% continuous filament nylon filling and a warp of 30% nylon staple/ 70% cotton was resin finished with Permafresh 183, a finishing agent useful for wrinkle proofing. The fabric area to be creased was marked by pressing the fabric for several seconds in a conventional Hoffman steam press. The superficially creased area was then wetted with an aqueous solution containing 11.1% benzyl alcohol and 25.2% ethyl alcohol. This solution was applied with a hand aerosol spray unit at the approximate rate of 2 cc. per gram of fabric. After spraying the crease area, the fabric was lagged on a hanger for 15 minutes. The area was then permanently creased by pressing in a New Yorker hot-head press for 20 seconds. The pressing temperature was 162 C. and the pressing cycle consisted of 2 seconds steam, 15 seconds bake, and 3 seconds vacuum. The pressure applied by the press head was 8.5 lbs./in. After pressing, the fabric was put in a heated oven at 162 C. for 12 minutes. This step completed drying of the crease area and cured the wrinkle-proofing resin. The resultant crease was sharp and had no puckering. After 10 home-type washing cycles, the crease received a panel rating of 3.7.

3 EXAMPLE II Crease Percent rating fabric Percent Percent Lag time, after 10 strength benzyl alcohol ethyl alcohol (min) wash. retained The minimum acceptable rating for crease retention is 3.0. The maximum acceptable percent loss in strength of the fabric as a result of the creasing treatment is 25 It will be understood that various changes in the details and steps which have been described and illustrated herein to explain the nature of the invention may be made by those skilled in the art within the principle and scope of the invention.

What is claimed is:

1. A process for imparting a durable crease to a textile material containing more than 50% polyamide fibers comprising:

(1) contacting the said textile material in the area where the crease is to be formed at a rate of about 2 cc. per gram of material with an aqueous solution 4 comprising 10 to 25% benzyl alcohol and 25 to ethyl alcohol,

(2) lagging the treated fabric for about 15 minutes prior to the application of heat, and

(3) forming the said crease by pressing said textile material at a temperature of to 170 C. for about 20 seconds.

2. Claim 1 wherein said contacting is accomplished by spraying the said textile material with the said aqueous solution.

3. Claim 1 wherein the said pressing comprises a 20 second cycle consisting of 2 seconds steam, 15 seconds bake, and 3 seconds vacuum at a temperature of about C.

4. Claim 1 wherein said pressing of the said textile material is followed by drying the said textile material in a heated oven at about 160 C. for about 12 minutes.

References Cited UNITED STATES PATENTS 2,157,118 6/1938 Heckert 264168 XR 2,157,119 5/1939 Miles.

2,285,967 6/1942 Hardy 18-56 2,957,746 1/1957 Buck 8-l29 3,025,622 3/1962 Hilton 38144 3,166,765 1/1965 Getchell 2227 3,341,955 9/1967 Pyke 38-144 ROBERT F. WHITE, Primary Examiner RICHARD R. KUCIA, Assistant Examiner US. Cl. X.R. 

